Malicious PDF — malware analysis report

Static analysis result for SHA-256 d4cd6770d65b7b83…

MALICIOUS

PDF

42.4 KB Created: 2020-09-02 06:52:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 24cbc5542a90cbf452ecfcd12f408f90 SHA-1: 061f8cf31971574ac8d3a1779cec012963961531 SHA-256: d4cd6770d65b7b839a9251fadd3bf9bf4270e1c6b73f539ee56465978e17b1f6
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by multiple critical heuristics for containing malicious redirector links and a link farm. The ML classifier also strongly indicated maliciousness. The primary malicious IOC is the URL 'https://ttraff.me/wix?keyword=acog+guidelines+colposcopy', which is part of a link farm pointing to various PDF files, likely to obscure the final malicious destination. The document body contains garbled text but includes the suspicious URL and references to other PDF files.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 4

  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://ttraff.me/wix?keyword=acog+guidelines+colposcopy
    • https://static.usrfiles.com/ugd/b80405_a69b0b1f9ef64bf5a51b0210cbdf465e.pdf
    • https://static.usrfiles.com/ugd/2ca09c_64b5a4cb019a46f19f9c5d0c7e8fbfd7.pdf
    • https://static.usrfiles.com/ugd/b8c837_dce3492ddc904da6843f81230637b7e9.pdf
    • https://static.usrfiles.com/ugd/3b7182_fe232531cdf847109576fbf69968b6a9.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/zupapinited.pdf
    • https://cdn.shopify.com/s/files/1/0429/1588/9305/files/jigarineporunawabi.pdf
    • https://cdn.shopify.com/s/files/1/0440/5687/1062/files/8547968059.pdf
    • https://cdn.shopify.com/s/files/1/0437/2440/6933/files/53636208163.pdf
    • https://cdn.shopify.com/s/files/1/0433/1739/5611/files/sociology_book_class_11.pdf
    • https://cdn.shopify.com/s/files/1/0437/7562/3320/files/laxaxixoziluw.pdf
    • https://cdn.shopify.com/s/files/1/0427/9818/6652/files/tunugefepapigavodexo.pdf
    • https://cdn.shopify.com/s/files/1/0440/7581/0966/files/pay_slip_request_letter_format.pdf
    • https://cdn.shopify.com/s/files/1/0430/7664/9124/files/90319358066.pdf
    • https://cdn.shopify.com/s/files/1/0431/8694/6206/files/28673764086.pdf
    • https://cdn.shopify.com/s/files/1/0449/7971/6264/files/aws_receive_billing_reports.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000676f.bin
22680ae092e46688fe5e3193a81d6e01c16ca8ef03aedb0f2045dad9e28bdc2f
pdf-font-stream PDF embedded font (sfnt) at offset 0x676F 5024 bytes
font_01_sfnt_off000078aa.bin
0867c3d746510266f9c9305f9c6ee33bef6507e62029f7ffc6026d1509f961cb
pdf-font-stream PDF embedded font (sfnt) at offset 0x78AA 10568 bytes